The present invention relates to the spectral analysis arts. It finds particular application to a portable color measuring device that is configured to receive and function with an independently operable processing device. It will be appreciated that the present invention will also find application to color measuring devices such as spectrophotometers, calorimeters, tristimulus calorimeters, single and multiple beam spectrophotometers, Gonio spectrophotometers and the like, and light emission type measuring devices.
Color measuring devices, such as spectrophotometers, are instruments used to determine the color of an object under test. They typically include a source of light that illuminates the object and a photodetector that detects and measures light signals reflected from the object. Then, signal processing circuitry connected to the photodetector computes curves or numerical values indicative of color. The general principles of construction and use of these instruments are well known and understood by those skilled in the art.
One known type of spectrophotometer uses an integrating sphere in which the light reflected from the object is integrated to obtain an average reading of the color over an exposed surface area of the object. Known integrating spheres can provide readings which represent xe2x80x9ctotalxe2x80x9d reflections or xe2x80x9cdiffuse-onlyxe2x80x9d reflections. The total reflections include all reflections from the exposed object, including specular reflections from the surface and diffuse reflections from particles in the body of the object. A xe2x80x9cdiffuse-onlyxe2x80x9d or specular-excluded measurement is obtained by excluding specular light that is reflected from the surface of the sample at an angle equal to the incident angle. This reflected light is referred to as the specular component. Exclusion of the specular component eliminates the light contribution due to gloss, and the color values obtained from a specular-excluded reading are independent of the glossiness of the surface of the object under test.
Typical bench-top or portable color measuring instruments include custom designed processing components such as a simple eight-bit processing unit and small amounts of memory. Most of the data processing function is performed by a remote personal computer that receives the measurement data from the spectrophotometer. Furthermore, the display is typically small and uses complicated menus and endless keystroke sequences to input and select data and request functions. Updating the device software requires a user to ship the entire spectrophotometer to the manufacturer. Overall, the device lacks flexibility and has limited processing power.
The present invention provides a new and unique color measuring device that cures the above problems and others.
In accordance with the present invention, a color measuring device for measuring color properties of an object is provided. The color measuring device includes a light source that transmits light onto the object. A sensor senses the light reflected from the object and generates electrical signals corresponding to the sensed light. The light source and the sensor are contained within a portable housing. The housing includes a mounting portion configured for mounting a portable independently operable computing device. An interface is configured to electrically connect a portable independently operable computing device to the portable housing and to communicate the electrical signals from the sensor to a portable independently operable computing device once mounted to the mounting portion and connected to the interface.
In accordance with a more limited aspect of the present invention, the color measuring device includes a portable independently operable computing device mounted to the portable housing and connected to the interface.
One advantage of the present invention is that a color measuring device can be produced in less time since custom made processing components and user interface and display are eliminated by configuring the color measuring device to mount an independently operatble computing device. With the present invention, the cost of manufacturing a color measuring device is also reduced.
Still further advantages of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the preferred embodiments.